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Abiogenesis - Chicken and Egg Paradox

QUESTION: Abiogenesis – What is the chicken and egg paradox?

ANSWER:

One of the most fundamental problems confronting adherents to the theory of abiogenesis is the chicken-and-egg paradox. DNA depends heavily on proteins for functioning, yet protein relies upon DNA for correct sequencing. Protein cannot arise apart from DNA, yet DNA requires proteins in order to function. Thus, the difficulty is: how did two independent systems -- both of which are necessary for the sustaining of life -- arise simultaneously that rely on one another for survival and function?

Some origin-of-life researchers have suggested that proteins may not have been the first building blocks of life and that DNA may not have been the first information storage medium. In recent years, scientists have suggested an ‘RNA-world’ model in which RNA serves as the precursor to both DNA and proteins. RNA has the capacity to store information (like DNA) and catalyze chemical reactions (like enzymes).

Abiogenesis and chicken and egg paradox
Yet no one has been able to demonstrate how RNA could have formed on the early earth in the absence of living cells. And besides, the sheer instability of the RNA molecule would render it unsustainable in the long-term.

Furthermore, there is no known naturalistic mechanism from the RNA world to the current DNA-protein world that fundamentally characterizes life as we know it.

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